Você sempre pode usar fração (para Oracle 1 =1 dia):
SELECT CURRENT_TIMESTAMP ,
CURRENT_TIMESTAMP + 200 *(1/24/60/60) AS addedTime
FROM dual;
<=>
SELECT CURRENT_TIMESTAMP + 200/86400 FROM dual
Demonstração do DBFiddle
ou:
SELECT CURRENT_TIMESTAMP + INTERVAL '200' SECOND FROM dual
